Differentiating Fire Regimes and Their Biophysical Drivers in Central Portugal
Rafaello Bergonse,
Sandra Oliveira,
José Luís Zêzere,
Francisco Moreira,
Paulo Flores Ribeiro,
Miguel Leal,
José Manuel Lima Santos
Affiliations
Rafaello Bergonse
Centre of Geographical Studies, Institute of Geography and Spatial Planning and Associate Laboratory TERRA, Universidade de Lisboa, Rua Branca Edmée Marques, Cidade Universitária, 1600-276 Lisbon, Portugal
Sandra Oliveira
Centre of Geographical Studies, Institute of Geography and Spatial Planning and Associate Laboratory TERRA, Universidade de Lisboa, Rua Branca Edmée Marques, Cidade Universitária, 1600-276 Lisbon, Portugal
José Luís Zêzere
Centre of Geographical Studies, Institute of Geography and Spatial Planning and Associate Laboratory TERRA, Universidade de Lisboa, Rua Branca Edmée Marques, Cidade Universitária, 1600-276 Lisbon, Portugal
Francisco Moreira
CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisbon, Portugal
Paulo Flores Ribeiro
Forest Research Centre, Instituto Superior de Agronomia, Universidade de Lisboa, Edifício Prof, Azevedo Gomes, Instituto Superior de Agronomia, Tapada da Ajuda, 1349-017 Lisbon, Portugal
Miguel Leal
Forest Research Centre, Instituto Superior de Agronomia, Universidade de Lisboa, Edifício Prof, Azevedo Gomes, Instituto Superior de Agronomia, Tapada da Ajuda, 1349-017 Lisbon, Portugal
José Manuel Lima Santos
Forest Research Centre, Instituto Superior de Agronomia, Universidade de Lisboa, Edifício Prof, Azevedo Gomes, Instituto Superior de Agronomia, Tapada da Ajuda, 1349-017 Lisbon, Portugal
We characterize fire regimes in central Portugal and investigate the degree to which the differences between regimes are influenced by a set of biophysical drivers. Using civil parishes as units of analysis, we employ three complementary parameters to describe the fire regime over a reference period of 44 years (1975–2018), namely cumulative percentage of parish area burned, Gini concentration index of burned area over time, and area-weighted total number of wildfires. Cluster analysis is used to aggregate parishes into groups with similar fire regimes based on these parameters. A classification tree model is then used to assess the capacity of a set of potential biophysical drivers to discriminate between the different parish groups. The results allowed us to distinguish four types of fire regime and show that these can be significantly differentiated using the biophysical drivers, of which land use/land cover (LULC), slope, and spring rainfall are the most important. Among LULC classes, shrubland and herbaceous vegetation play the foremost role, followed by agriculture. Our results highlight the importance of vegetation type, availability, and rate of regeneration, as well as that of topography, in influencing fire regimes in the study area, while suggesting that these regimes should be subject to specific wildfire prevention and mitigation policies.
